一例异位脑膜瘤报道并文献复习

A case report of extracranial meningioma and literature review

目的 探讨1例异位脑膜瘤(EM)的临床病理特征、免疫表型、鉴别诊断及临床预后。方法 对1例EM病例进行光学显微镜下组织学观察,采用EnVision法染色观察EM免疫表型并进行鉴别诊断。结果 EM组织学与颅内脑膜瘤组织学结构相似,肿瘤包膜完整,本例EM镜下特点为过度型脑膜瘤:脑膜皮细胞型+砂粒体型,肿瘤细胞呈实性片状、巢团状分布,巢团间有纤维性分隔,肿瘤细胞大小一致,细胞胞界不清,染色质弱嗜酸性、细腻,核呈圆形或卵圆形,核仁不清。漩涡状结构易见,可见砂粒体。免疫表型示Vimentin(+)、EMA弱(+)、PR(+)、S-100(-)、GFAP(-)、CD34(-)、Bcl-2(-)、CD99(-)、STAT6(-)、SOX10(-)、CgA(-)、Syn(-)及Ki-67阳性率3%~5%。结论 EM作为罕见病例,组织学特点与颅内脑膜瘤组织学特征相似,需结合组织学特征及免疫组化特点进行明确诊断。

Objective To explore the clinicopathological features,immunophenotype,differen⁃tial diagnosis and clinical prognosis in one case of extracranial meningioma(EM).Methods One case of E⁃M was observed histologically under microscope,and the EM immunophenotype was observed by EnVision staining for differential diagnosis.Results The histological structure of EM is similar to that of intracranial meningioma.The tumor capsule is completed,this case is characterized by transitional meningioma:meningo⁃thelial type and psammomatous type.The tumor cells are distributed in solid flakes and nests,with fibrous sep⁃aration between nests.The tumor cells have the same size,unclear cell boundary,weak eosinophilic chroma⁃tin,fine chromatin,round or oval nucleus and unclear nucleolus.Vortex structure is easy to see,and sand par⁃ticles can be seen.Immunophenotype showes that Vimentin+,EMA+(weak),PR+,S⁃100⁃,GFAP⁃,CD34⁃,Bcl⁃2⁃,CD99⁃,STAT6⁃,SOX10⁃,CgA⁃,Syn⁃,the positive rate of Ki⁃67 was 3%~5%.Conclusion As a rare case,the histological characteristics of EM are similar to those of intra cranial meningioma,which should be clearly diagnosed in combination with histological and immunohisto chemical characteristics.